Queue32

Queue32.c

// Queue32.c
// 4byte ring buffer (32bit version)
//
// 2016.07.27 : D.F.Mac.

#include "queue32.h"

#ifdef __cplusplus
extern "C"{
#endif 

void b4arrq_init(stB4Arrq *qp){
  qp->top = 0;
  qp->last = 0;
  qp->num = 0;
  qp->queue_size = B4QUEUE_SIZE;
}

uint32_t b4arrq_next(uint32_t value){
  return (value + 1) % B4QUEUE_SIZE;
}

uint32_t b4arrq_push(stB4Arrq *qp, uint32_t *p){
  uint32_t *q = qp->queue;
  uint32_t last = qp->last;
  if(b4arrq_next(last) == qp->top){
    return 0;
  }
  *(q+last) = *p;
  qp->last = b4arrq_next(last);
  qp->num ++;
  return 1;
}

uint32_t *b4arrq_pop(stB4Arrq *qp){
  uint32_t *pRes = (uint32_t *)0;
  uint32_t *p = qp->queue;
  uint32_t top = qp->top;
  if(top != qp->last){
    pRes = p+top;
	qp->top = b4arrq_next(top);
	qp->num --;
  }
  return pRes;
}

#ifdef __cplusplus
} // extern "C"
#endif

Queue32.h

// Queue32.h
// 4byte ring buffer (32bit version)
//
// 2016.07.27 : D.F.Mac.

#ifndef __queue32_h__
#define __queue32_h__

#include <stdint.h>

#ifdef __cplusplus
extern "C"{
#endif 

#define B4QUEUE_SIZE 512

typedef struct{
  uint32_t top;
  uint32_t last;
  uint32_t num;
  uint32_t queue_size;	// not use yet.
  uint32_t queue[B4QUEUE_SIZE];
}stB4Arrq;

void b4arrq_init(stB4Arrq *qp);
uint32_t b4arrq_push(stB4Arrq *qp, uint32_t *p);
uint32_t *b4arrq_pop(stB4Arrq *qp);

#ifdef __cplusplus
} // extern "C"
#endif

#endif